A plurality of fast, high performance imaging lenses to be used in imaging apparatuses that employ imaging elements such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) as recording media, such as video cameras and electronic still cameras, have been proposed in the past. Among such imaging lenses, the Gauss type of imaging lens is particularly well known, and several imaging lenses having F numbers from 1.2 to approximately 2.8 have been proposed.
For example, Japanese Unexamined Patent Publication No. 6(1994)-242370 proposes an imaging lens having an F number of 1.4. In addition, an imaging lens designed to reduce the weight of focusing lenses by adopting a rear focusing configuration is proposed in Japanese Unexamined Patent Publication No. 9(1997)-049968.